<!DOCTYPE html>
<meta charset="UTF-8">
<iframe></iframe>
<script>
(async () => {
var blob = await fetch('green.bmp').then(r => r.blob());
var urlBg = URL.createObjectURL(blob);

var frameText = `\
<!DOCTYPE html>
<style>img { width: 60px; }<\/style>
<img src="${urlBg}">`;
var blob = new Blob([frameText], {type: 'text/html'});
var urlFrame = URL.createObjectURL(blob);

document.querySelector('iframe').src = urlFrame;
})();
</script>
